Grand Teton grizzlies make rare cub exchange
AP Pho
FILE - This May 2011 file photo shows Grizzly bear No. 610 walking through sagebrush in Grand Teton National Park, Wyo., while her two cubs look on. A grizzly bear in Grand Teton National Park has wowed scientists and tourists alike by adopting a cub from another sow grizzly. Park officials say they are fairly certain that No. 610 has adopted one of her younger siblings: No. 610 is the 5-year-old daughter of No. 399. Park officials say such behavior is not unprecedented but quite rare.
A grizzly bear in Grand Teton National Park has wowed scientists and tourists alike by adopting a cub from another sow grizzly.Park officials say such behavior is rare but not unprecedented. The switch is especially fascinating for having occurred between two grizzlies that are well-known — famous, practically — in the region for having spent so much time this summer near roads and developed areas where they've been easy to observe with their cubs.
What's more, the bears are keeping it in the family: The adopting mother grizzly is the daughter of the grizzly that lost its cub.
"For the general public to find out that something like this could happen I think is a fascinating glimpse into bear behavior and what can happen among bears that are related," Grand Teton spokeswoman Jackie Skaggs said Monday.
The switch occurred between a 15-year-old grizzly that biologists identified years ago with the number 399 and her daughter, a 5-year-old grizzly identified by the number 610.
Grizzly No. 610 gave birth to two cubs last winter. She has been seen with a third cub since late last week. Grizzly No. 399 gave birth to three cubs last winter but in the past few days has been seen with just two cubs in tow.
Research has shown that grizzlies sometimes will adopt cubs that become separated from their mothers. Separation can occur after a disturbance of some kind.A brief separation apparently happened last month in the family of No. 610, when the mother grizzly was seen without her cubs and behaving in an agitated manner. She was spotted with her cubs again soon after, Skaggs said.
Some speculated a male grizzly might have disrupted the family. Each summer around June, male grizzlies are known to kill cubs to cause their mothers to go into estrus, when females are receptive to mating, Skaggs said.
Nobody knows how No. 399 might have become separated from her cub. But the switch occurred around the same time as reports of the sound of bears fighting in her territory last Thursday night, park biologist Steve Cain said.
Scientists haven't confirmed beyond a shadow of a doubt, such as through DNA testing, that the new cub following No. 610 is the one lost by No. 399.
"The possibility exists that 399 lost a cub by another means and 610 gained one by a different family group," Cain said. "But I would characterize that possibility as extremely low."
While previous research has documented grizzlies swapping cubs in Yellowstone National Park, Cain said he's never seen it in Grand Teton."It probably occurs in the wild more frequently than is ever documented because it's a difficult type of occurrence to document," he said.
The mother-daughter grizzlies have overlapping territories not far from Jackson Lake Dam toward the northeast side of Grand Teton. The grizzlies spend a fair amount of time within sight of park roads. One theory is males keep their distance when the females are closer to people.
The grizzlies have caused a number of traffic jams of tourists thrilled by the chance to watch and photograph the bear families.
Longtime wildlife watchers have been eager to see if No. 399 and No. 610 will ever cross paths and interact. Each grizzly seems to be aware that the other is roaming the same part of the park, Skaggs said, but the bears have yet to be spotted in the same place at the same time.
What's more, the bears are keeping it in the family: The adopting mother grizzly is the daughter of the grizzly that lost its cub.
"For the general public to find out that something like this could happen I think is a fascinating glimpse into bear behavior and what can happen among bears that are related," Grand Teton spokeswoman Jackie Skaggs said Monday.
The switch occurred between a 15-year-old grizzly that biologists identified years ago with the number 399 and her daughter, a 5-year-old grizzly identified by the number 610.
Grizzly No. 610 gave birth to two cubs last winter. She has been seen with a third cub since late last week. Grizzly No. 399 gave birth to three cubs last winter but in the past few days has been seen with just two cubs in tow.
Research has shown that grizzlies sometimes will adopt cubs that become separated from their mothers. Separation can occur after a disturbance of some kind.A brief separation apparently happened last month in the family of No. 610, when the mother grizzly was seen without her cubs and behaving in an agitated manner. She was spotted with her cubs again soon after, Skaggs said.
Some speculated a male grizzly might have disrupted the family. Each summer around June, male grizzlies are known to kill cubs to cause their mothers to go into estrus, when females are receptive to mating, Skaggs said.
Nobody knows how No. 399 might have become separated from her cub. But the switch occurred around the same time as reports of the sound of bears fighting in her territory last Thursday night, park biologist Steve Cain said.
Scientists haven't confirmed beyond a shadow of a doubt, such as through DNA testing, that the new cub following No. 610 is the one lost by No. 399.
"The possibility exists that 399 lost a cub by another means and 610 gained one by a different family group," Cain said. "But I would characterize that possibility as extremely low."
While previous research has documented grizzlies swapping cubs in Yellowstone National Park, Cain said he's never seen it in Grand Teton."It probably occurs in the wild more frequently than is ever documented because it's a difficult type of occurrence to document," he said.
The mother-daughter grizzlies have overlapping territories not far from Jackson Lake Dam toward the northeast side of Grand Teton. The grizzlies spend a fair amount of time within sight of park roads. One theory is males keep their distance when the females are closer to people.
The grizzlies have caused a number of traffic jams of tourists thrilled by the chance to watch and photograph the bear families.
Longtime wildlife watchers have been eager to see if No. 399 and No. 610 will ever cross paths and interact. Each grizzly seems to be aware that the other is roaming the same part of the park, Skaggs said, but the bears have yet to be spotted in the same place at the same time.
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